When were sunglasses invented? The first sunglasses were used by the Inuit people tens of thousands of years ago. The Inuit people lived, and still live, on the Arctic regions of Greenland, Canada, and Alaska. Snow blindness is a problem that they have always had to deal with. Snow blindness is not caused by the […]
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What is the densest material in the universe? Osmium is the densest material on Earth, but the densest material in the universe (that we know of) is that of a neutron star. What is density? Density is the amount of mass that something has in relation to the space that it occupies. For example, a
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What were the moa and what happened to them? The South Island Giant Moa was a 3.6 m tall bird that were hunted to extinction by 1445. The Moa were flightless birds that lived in New Zealand. They were very similar to ostriches, but about a meter taller. When they stretched their necks up, the
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Why is oil measured in barrels? Oil is measured in barrels because that was the size of a wine barrel in 1866. Nobody really knows when barrels were invented, but there is a picture of a wooden barrel made to measure wheat on the wall of the tomb of the Egyptian high official, Hesy-Ra, from about
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What are contact lenses made of? Soft contact lenses are made of an oxygen permeable soft plastic. Hard lenses are made of a plastic like Perspex. There are generally two types of contact lenses: soft and hard. Soft lenses are made of a soft plastic. These days, the plastic used is silicone hydrogel. Silicone hydrogel
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Why is Christmas on December 25th? No one really knows, but there are several theories. Christmas is the day to celebrate the birth of Christ in a lot of the world. It is traditionally celebrated on December 25th, but there is no actual evidence for this date. The only accounts for the birth of Jesus
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When did people start having lawns outside their houses? Probably from the early 16th century. The first use of the word “laune” is in 1540. We need to differentiate between lawn and garden here because people have been gardening for thousands of years. A garden has basically been a space in front of a dwelling
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What causes thunder? Thunder is caused because the air around a lightning bolt is superheated. Lightning is caused when there is an imbalance in the electrical charge within clouds. During a heavy storm, strong winds circulate through storm clouds. The wind picks up water droplets at the bottom and carries them to the top of
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Was there really going to be a black Taj Mahal? The idea of a black Taj Mahal to go with the white one is probably just a myth as there is no actual evidence for it. The Taj Mahal was built by the Mughal emperor, Shah Jahan, and was finished in 1653. It is a
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How does wireless charging work? By sending power from a transmitter to a receiver. Wireless charging is known as inductive charging and it is very common these days. Many of us charge our phones by placing them on a magnetic wireless charging pad. But, how does wireless charging work? It uses something called inductive charging.
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